Bug#169818: libc6: runlevel can return «unknown», which breaks restarts

[Tollef Fog Heen <tollef@add.no>]

Package: libc6
Severity: grave
Justification: breaks upgrades completely in chroots.

The check in libc6's postinst checks if it should restart a service in
the current runlevel.  However, in some cases, it returns «unknown»,
which breaks the script completely.

Package `snmpd' is not installed and no info is available.
Package `ssh-krb5' is not installed and no info is available.
Package `apache2' is not installed and no info is available.
Package `samba' is not installed and no info is available.
Package `courier-authdaemon' is not installed and no info is available.
Use dpkg --info (= dpkg-deb --info) to examine archive files,
and dpkg --contents (= dpkg-deb --contents) to list their contents.
sed: can't read cron: No such file or directory
dpkg: error processing libc6 (--configure):
 subprocess post-installation script returned error exit status 2
Errors were encountered while processing:
 libc6
E: Sub-process /usr/bin/dpkg returned an error code (1)
bin/sh-2.05b#

Also, when none of the services which are to be restarted are present,
one needs to send EOF in order for the postinst to continue, since sed
tries to read from stdin.

-- 
Tollef Fog Heen                                                        ,''`.
UNIX is user friendly, it's just picky about who its friends are      : :' :
                                                                      `. `' 
                                                                        `-